Improvement in valves foe steam engines



@geiten taten @anni @fitte 'IMPROVBMBNT'IN VALVES roe STEAM internes.

@te tttttle rlfetrct it it tigen Enters @tout mit mating tart tf tige time Be it known that I,` JAMES A. WODBURY, of Boston, in the county of Suffolk, and Stat-e of Massachusetts, have invented a new and useful Improvement in Balanced Slide-Valves for Steam Engines, oi'nwhioh the follown ing is a full, clear, and exact description, reference boing had to thc accompanying drawings, making a part of this specification, in whiehl Figure 1 represents a longitudinal vertical section of a cylinder and steam chest containing my improvement.

p Figure 2 is a transverse vertical section of the same.

Figure Slis a view of the valves and connecting cross-head g and Figure 4 is a longitudinal'vertical section on the line y y ot iig. f2

Similar letters represent like parts in thc several figures. p

This invention is designed more particularly as an improvement Vin slide-valves, for which a patent was granted to me on July .4, 1865, and it consists in so constructing two or more valves and combining them with wall ports, as that they may form four or more openings without any outside pressure of steam upon the valves, the parts of the valves being filled independently of each other, andvso arranged as to admit of the free contraction and expansion ofthe walls and valves.

Referring to the drawings, A represents the cylinder, and B the steam chest. Within the steam chest are arrangedl the side walls, one, c', atthc centre, and -one, c, at each end, containing respectively the inlet ports a a', and exhaust ports b b. The inlet ports communicate with the steam cylinder through the steam passages c c', and the passage d connects with the exhaust in the usual manner. The steam valves D D are nrrangcdon either side of the central wall c', and are formed with their sides inclining inwardly from top to bottom, as shown in gs. 2 and 3. Extending across the top ot' cach valve, and itting loosely 'inn slotpor groove in the same, is a cross-hcad, 7s, which is secured in place by means of cops, it', so as to admit of expansion or contraction of thc valves between the walls," A valve-rod, Z, is attached to the cross-headvc inany suitable manner. v On .the under sido of each of the'valvesD D', 'a groove or recess, "1L it', for the purpose of admitting steam to that portion of the valves, and thus cause the same to serve asa balance valve; the steam acting with nearly uniform pressure upon all sides of the valves. The valves are ground or scraped upon their sides or bearings, so that they will not be liable to become loose or leaky. Steam is introduced iroinithe boiler into the passage E, and the exhaust steam passes oit at F. I have shown and described but two valves andthrce openings, but thenumber of each may be increased with the increased size of the cylinder, 'either by arranging them side hy side, with one wall between every two valves, or by placing dii'crent sets at either end of the cylinder. `My invention is equally applicable to` horizontal, upright, or inclined cylinders.

What I claim as new, and desire to securcrby Letters Patent, is

The combination of two or more valves with intermediate walls when constructed and operating substantially as and for the purpose set forth.

I* In tcstimonv whcreoi` I have signed my 'nume to this specification in thc presence of two subscribing witnesses.

JAMES A. WooDnUnY.

Witnesses:

J. H. ADAMS, WILLIAM E. Loonwoon, 

